Folder
Engineering Investigation

2018 Engineering Investigation Status

The District has received data from producers for its 2018 Final Engineering Investigation Report. Staff has completed entering and performing analysis and QA/QC and produced the Report and Appendices. All reports are shown below.

Each year since 1993, the District has produced an Engineering Investigation in accordance with Article 1, Section 75560 of the California Water Code which requires that a Water Conservation District that proposes to levy a groundwater charge "... shall annually cause to be made an engineering investigation and report upon groundwater conditions of the District". In accordance with these requirements, the San Bernardino Valley Water Conservation District must make the following findings and determinations as they relate to the ground and surface water conditions of the Bunker Hill Basin and those areas within the District boundary.

Task 1. Annual change in storage for the Bunker Hill Basin for the preceding water year;Task 2. Accumulated change in storage of the Bunker Hill Basin as of the last day of the preceding water year;Task 3. Total groundwater production from the Bunker Hill Basin for the preceding water year;Task 4. Estimate of the annual change in the Bunker Hill Basin storage for the current water year;Task 5. Estimate of the annual change in the Bunker Hill Basin storage for the ensuing water year;Task 6. Average annual change in Bunker Hill Basin storage for the immediate past ten water years;Task 7. Estimated amount of agricultural water and non-agricultural water to be withdrawn from the groundwater supplies of the District for the ensuing water year;Task 8. Estimated amount of water necessary for surface distribution for the ensuing water year for the Bunker Hill Basin and the District; andTask 9. The amount of water that is necessary for the replenishment of the groundwater supplies of the Bunker Hill Basin and the District for the ensuing water year .

To make the findings and determinations listed above, District staff researched available hydrogeologic and engineering data for the Bunker Hill Basin. The data was compiled and analyzed and a predictive relationship between precipitation, production, and change in basin storage was determined. This relationship was based on empirical data since 1993 and enables the prediction of change in storage given certain annual production and precipitation levels. In addition, annual and accumulated change in storage values were calculated based on current and historic water level changes throughout the Bunker Hill Basin.

With the support of producers in the basin, the Report is compiled and posted for review and comment. Staff receives many comments from the Board and from basin stakeholders and incorporates these into the final version for the April Public Workshop. All basin agencies cooperate in providing groundwater production and groundwater levels. The report contains wells identified by staff and located in GIS. The report also contains some data marked as provisional or documented assumptions, but represents the best available data and professional judgment. SBVMWD also runs their model for the basin to compare with the EI Report; historically it has coroborated the results of the EI.